Fill levels can be measured by evaluating reflections or echoes of guided microwaves or guided radar waves. For this purpose, waves or signals propagate along a probe within a container and are reflected when they come into contact with a filling material or with air. These reflections can be identified as echoes in an echo diagram. By surveying the intervals of the echoes obtained during this measurement, the fill level within the container can be determined; in particular, it can be determined whether the container is empty, in other words merely full of air. Generally, a level measurement is carried out when the probe touches the medium or is dipped into the medium. The waveguides used in guided-microwave level measurement are basically cables which are part of a cable probe. A cable probe comprises a tightening weight at one end thereof so as to provide a maximally stable position of the cable probe within the container.
However, the tightening weights used for the tightening may themselves influence the measurement results. Often, they are in the form of solid, substantially cylindrically shaped weights. The weights are basically produced with a view to a high mass, meaning that they often have a large diameter by comparison with the waveguide.